Pi-Star

Jonathan G4KLX’s distro offers the option to use MMDVM based hotspots as POCSAG transmitter. The hotspot will connect to the DAPNET and during idle time it will transmit pager messages in the designated time slots

This only works with MMDVM based hotspots. DVMega doesn’t support this!

What you need:

  • MMDVM based hotspot (i.e. MMDVM_HS_HAT)
  • DAPNET user account
  • DAPNET transmitter account

Accounts can be requested by raising a tichet at the DAPNET-support website.

Pi-Star setup

Download the Pi-Star distribution and write it to an SD card. There are plenty of step by step manuals how to do this. Furthermore it comes handy to prepare a ‘wpa_supplicant.conf’ file using the  Pi-Star Tools-page. The file you create has to be put into the boot directory of the SD card using an SD card reader. That’s the last step before putting the SD card into the Raspberry. By that step the Raspberry gets the credentials for the wifi network, so it can connect immediately during boot.

Configuration of the correct modem type, DMR, DStar etc. are not covered in this explanation. Beside the fact it’s quite self explaining, a lot of information can be found at the internet.

The ‘Configuration’ menu of Pi-Star contains a section ‘POCSAG Configuration’. The server is set to the Aachen University node by default. The box ‘Node Callsign’ can be a bit confusing, but here you enter your transmitter callsign. ‘DAPNET AuthKey’ contains the ‘AuthKey’ of the corresponding transmitter. These credentials are to be requested at the DAPNET support team by raising a ticket. So you can’t use the same credentials for your hotspot as you use to login to the DAPNET website! Don’t activate the POCSAG function of the hotspot before you’ve received the transmitter credentials from the support team. A hotspot will keep trying to login to the node, but after a number of unsuccessful attempts the IP address will be blocked to stop this unwanted mini-DDOS attack

Switch to a different DAPNET-node

As the node of Aachen University is the only available option in Pi-Star, all MMDVM hotspots worldwide will connect this server. This leads to a huge server load. But with some jiggery pokery it’s possible to switch to another node (probably closer to your own region).

  • connect the hotspot using SSH
  • become root user (‘sudo su’) – be carefull: you’re in god mode!
  • now make the file system writable (‘mount -o remount,rw /’)
  • open the file /etc/dapnetgateway using your favorite editor (i.e. ‘nano /etc/dapnetgateway’)
  • ook for the line ‘Address’ in the section ‘[DAPNET]’ and replace the server address by another core, i.e. ‘dapnet.hampager.be’
  • save the  file and quit the editor
  • reboot your hotspot (‘reboot’)